<template>
  <div class="app-container">
    <el-button type="primary" @click="handleAddRole">New Role</el-button>
    <el-table :data="rolesList" style="width: 100%; margin-top: 30px" border>
      <el-table-column align="center" label="Role Key" width="220">
        <template slot-scope="scope">
          {{ scope.row.key }}
        </template>
      </el-table-column>
      <el-table-column align="center" label="Role Name" width="220">
        <template slot-scope="scope">
          {{ scope.row.name }}
        </template>
      </el-table-column>
      <el-table-column align="header-center" label="Description">
        <template slot-scope="scope">
          {{ scope.row.description }}
        </template>
      </el-table-column>
      <el-table-column align="center" label="Operations">
        <template slot-scope="scope">
          <el-button type="primary" size="small" @click="handleEdit(scope)">Edit</el-button>
          <el-button type="danger" size="small" @click="handleDelete(scope)">Delete</el-button>
        </template>
      </el-table-column>
    </el-table>

    <el-dialog
      :visible.sync="dialogVisible"
      :title="dialogType === 'edit' ? 'Edit Role' : 'New Role'"
    >
      <el-form :model="role" label-width="80px" label-position="left">
        <el-form-item label="Name">
          <el-input v-model="role.name" placeholder="Role Name" />
        </el-form-item>
        <el-form-item label="Desc">
          <el-input
            v-model="role.description"
            :autosize="{ minRows: 2, maxRows: 4 }"
            type="textarea"
            placeholder="Role Description"
          />
        </el-form-item>
        <el-form-item label="Menus">
          <el-tree
            ref="tree"
            :check-strictly="checkStrictly"
            :data="routesData"
            :props="defaultProps"
            show-checkbox
            node-key="path"
            class="permission-tree"
          />
        </el-form-item>
      </el-form>
      <div style="text-align: right">
        <el-button type="danger" @click="dialogVisible = false">Cancel</el-button>
        <el-button type="primary" @click="confirmRole">Confirm</el-button>
      </div>
    </el-dialog>
  </div>
</template>

<script>
import path from 'path';
import { deepClone } from '@/utils';
import { getRoutes, getRoles, addRole, deleteRole, updateRole } from '@/api/role';

const defaultRole = {
  key: '',
  name: '',
  description: '',
  routes: [],
};

export default {
  data() {
    return {
      role: Object.assign({}, defaultRole),
      routes: [],
      rolesList: [],
      dialogVisible: false,
      dialogType: 'new',
      checkStrictly: false,
      defaultProps: {
        children: 'children',
        label: 'title',
      },
    };
  },
  computed: {
    routesData() {
      return this.routes;
    },
  },
  created() {
    this.getRoutes();
    this.getRoles();
  },
  methods: {
    async getRoutes() {
      const res = await getRoutes();
      this.serviceRoutes = res.data;
      this.routes = this.generateRoutes(res.data);
    },
    async getRoles() {
      const res = await getRoles();
      this.rolesList = res.data;
    },

    // Reshape the routes structure so that it looks the same as the sidebar
    generateRoutes(routes, basePath = '/') {
      const res = [];

      for (let route of routes) {
        // skip some route
        if (route.hidden) {
          continue;
        }

        const onlyOneShowingChild = this.onlyOneShowingChild(route.children, route);

        if (route.children && onlyOneShowingChild && !route.alwaysShow) {
          route = onlyOneShowingChild;
        }

        const data = {
          path: path.resolve(basePath, route.path),
          title: route.meta && route.meta.title,
        };

        // recursive child routes
        if (route.children) {
          data.children = this.generateRoutes(route.children, data.path);
        }
        res.push(data);
      }
      return res;
    },
    generateArr(routes) {
      let data = [];
      routes.forEach((route) => {
        data.push(route);
        if (route.children) {
          const temp = this.generateArr(route.children);
          if (temp.length > 0) {
            data = [...data, ...temp];
          }
        }
      });
      return data;
    },
    handleAddRole() {
      this.role = Object.assign({}, defaultRole);
      if (this.$refs.tree) {
        this.$refs.tree.setCheckedNodes([]);
      }
      this.dialogType = 'new';
      this.dialogVisible = true;
    },
    handleEdit(scope) {
      this.dialogType = 'edit';
      this.dialogVisible = true;
      this.checkStrictly = true;
      this.role = deepClone(scope.row);
      this.$nextTick(() => {
        const routes = this.generateRoutes(this.role.routes);
        this.$refs.tree.setCheckedNodes(this.generateArr(routes));
        // set checked state of a node not affects its father and child nodes
        this.checkStrictly = false;
      });
    },
    handleDelete({ $index, row }) {
      this.$confirm('Confirm to remove the role?', 'Warning', {
        confirmButtonText: 'Confirm',
        cancelButtonText: 'Cancel',
        type: 'warning',
      })
        .then(async () => {
          await deleteRole(row.key);
          this.rolesList.splice($index, 1);
          this.$message({
            type: 'success',
            message: 'Delete succed!',
          });
        })
        .catch((err) => {
          console.error(err);
        });
    },
    generateTree(routes, basePath = '/', checkedKeys) {
      const res = [];

      for (const route of routes) {
        const routePath = path.resolve(basePath, route.path);

        // recursive child routes
        if (route.children) {
          route.children = this.generateTree(route.children, routePath, checkedKeys);
        }

        if (checkedKeys.includes(routePath) || (route.children && route.children.length >= 1)) {
          res.push(route);
        }
      }
      return res;
    },
    async confirmRole() {
      const isEdit = this.dialogType === 'edit';

      const checkedKeys = this.$refs.tree.getCheckedKeys();
      this.role.routes = this.generateTree(deepClone(this.serviceRoutes), '/', checkedKeys);

      if (isEdit) {
        await updateRole(this.role.key, this.role);
        for (let index = 0; index < this.rolesList.length; index++) {
          if (this.rolesList[index].key === this.role.key) {
            this.rolesList.splice(index, 1, Object.assign({}, this.role));
            break;
          }
        }
      } else {
        const { data } = await addRole(this.role);
        this.role.key = data.key;
        this.rolesList.push(this.role);
      }

      const { description, key, name } = this.role;
      this.dialogVisible = false;
      this.$notify({
        title: 'Success',
        dangerouslyUseHTMLString: true,
        message: `
            <div>Role Key: ${key}</div>
            <div>Role Nmae: ${name}</div>
            <div>Description: ${description}</div>
          `,
        type: 'success',
      });
    },
    // reference: src/view/layout/components/Sidebar/SidebarItem.vue
    onlyOneShowingChild(children = [], parent) {
      let onlyOneChild = null;
      const showingChildren = children.filter((item) => !item.hidden);

      // When there is only one child route, the child route is displayed by default
      if (showingChildren.length === 1) {
        onlyOneChild = showingChildren[0];
        onlyOneChild.path = path.resolve(parent.path, onlyOneChild.path);
        return onlyOneChild;
      }

      // Show parent if there are no child route to display
      if (showingChildren.length === 0) {
        onlyOneChild = { ...parent, path: '', noShowingChildren: true };
        return onlyOneChild;
      }

      return false;
    },
  },
};
</script>

<style lang="scss" scoped>
.app-container {
  .roles-table {
    margin-top: 30px;
  }
  .permission-tree {
    margin-bottom: 30px;
  }
}
</style>
